Coupling assembly for fluid lines

ABSTRACT

A coupling assembly for releasably interconnecting fluid passages comprises male and female coupling members, which are mated by inserting a probe and socket of the members respectively. Each coupling member has a first end arranged for connection to a fluid passage. When mated in use, the coupling assembly provides a straight fluid conduit between the fluid passages comprising through-bores in each of the coupling members coincident along a first longitudinal axis. When mated in use, the probe and socket are arranged coincident on a second longitudinal axis, which is inclined to the first axis. Sealing means comprising an annular sealing ring proximate each of the socket and probe are arranged, when mated in use, either side of an intersection between the through-bore and socket. The sealing arrangement is such that fluid within the fluid conduit exerts a net force resisting separation of said coupling members.

TECHNICAL FIELD AND BACKGROUND OF THE INVENTION

The present invention relates to a coupling assembly and in particularto a coupling assembly suitable for releasably interconnecting fluidpassages.

It is a common requirement in many industries to be able to quickly andreleasably interconnect two passages (e.g. pipes or hoses) containingfluids. The range of fluids to be transported, together with theirproperties, may vary widely, including gases such as air within medicaloxygen masks and liquids such as oil within undersea drillingoperations. The pressure of the fluid passing through the couplingassembly may vary from substantially the same as the ambient pressurearound the assembly in the case of oxygen masks to high-pressure liquidsat pressures many times the ambient pressure in the case of oilpipelines.

A number of quick release coupling arrangements are known in the artwhereby the ends of fluid passages are provided with correspondingcoupling members to facilitate the joining of passages. This may beprovided in the form of a female coupling member comprising a socket anda corresponding male coupling member comprising a probe receivable inthe socket. The coupling members may further be provided with breakoutvalves such that when the male and female coupling members are uncoupledthe ends are sealed off preventing fluid from escaping.

However, releasable coupling arrangements comprising a socket and probecan create large separation forces, which act to expel the male andfemale coupling members apart. The separation force is generated due tothe pressure of the fluid within the coupling assembly exerting apressure upon the end portion of the male coupling member and istherefore a product of the pressure and cross-sectional area of theprobe at the point where it exits the socket. Consequently, theseparation force quickly becomes large with high-pressure fluids andlarge diameters. When the separation force becomes greater than thefrictional force retaining the coupling parts together, it is necessaryto incorporate an additional form of mechanical retention in order toprevent the coupling assembly from uncoupling.

However, such mechanical retention devices may be required to breakunder a predetermined force applied to the coupling assembly. Forinstance, for air-to-air refueling operations a tanker aircraft trails afuel pipeline. At the end of the pipeline remote from the tankeraircraft is a drogue, which comprises the female coupling member. Theaircraft to be refueled is fitted with a forward extending probe, theend of which forms the male coupling member. In order to prevent thecoupling assembly from pulling apart during turbulence and with smallchanges in relative position of the aircraft, the coupling assembly mustincorporate some form of retention means. However, in an emergencysituation it is essential that the coupling releases under apredetermined force. This force is known as the breakout strength.

This desired breakout strength may be relatively low compared with thestrength of the mechanical retention device used to overcome theseparation force exerted upon the male member by the fluid within thecoupling assembly. Consequently, this can lead to the retention devicebeing constrained to only break or release under a higher applied forcethan would ideally be desirable, due to the design tolerances of theretention device.

The mechanism used to counteract the separation force of a couplingassembly can be separate from the mechanism used to provide the breakoutstrength, in order that the breakout strength may be set independently.

It is known to reduce the separation forces within coupling assembliesby arranging the assembly such that in addition to, and counteracting,the separation force created by the fluid, a force acting to resistseparation is created by the fluid. The coupling assembly is arrangedsuch that it comprises an internal surface upon which fluid exertspressure of equal area to the cross sectional area of the male couplingmember where it exits the female coupling member. Consequently thecoupling is said to be “pressure balanced”, effectively resulting in azero net separation force due to the internal fluid pressures.

Currently however, releasable coupling arrangements include protrusionsand fluid paths that create turbulence when transmitting fluid betweenone conduit or pipe to another. It is also not possible to ‘pig’ suchcouplings, which is a requirement in the oil transmission industry andconsists of moving a device through the inside of a pipe line for thepurpose of cleaning, dimensioning, or inspecting.

SUMMARY OF THE INVENTION

It is an object of the current invention to attempt to overcome at leastone of the above or other disadvantage.

According to one aspect of the present invention a coupling assembly forreleasably interconnecting fluid passages comprises male and femalecoupling members, which are mated in use by inserting a probe of themale member into a socket of the female member, each coupling memberincluding a first end arranged for connection to a fluid passage and athrough bore extending from the first end, wherein when mated in use,the through-bores of each coupling member are coincident along a firstlongitudinal axis and the probe and socket are coincident along a secondlongitudinal axis, which is inclined to the first axis, thethrough-bores providing a fluid conduit between the two fluid passagesand fluid being substantially retained in the conduit by sealing means.

Preferably the angle of inclination between the first and secondlongitudinal axes is between 5° and 35°. Preferably the angle ofinclination between the first and second longitudinal axes is between10° and 30°. Preferably the angle of inclination between the first andsecond longitudinal axes is between 15° and 25°.

Preferably the sealing means may comprise a first and second annularsealing ring. The sealing rings may be arranged in use to be either sideof an intersection between the through-bores and socket. The sealingrings may both be external annular sealing rings on the probe, such thatno net separation force is generated. Alternatively, the sealing ringsmay both be internal annular sealing rings within the socket, such thatno net separation force is generated. However, preferably the firstannular sealing ring may comprise an internal annular sealing ringwithin the socket and the second annular sealing ring may comprise anexternal annular sealing ring on the probe, such that fluid within thefluid conduit exerts pressure on the internal surfaces to provide a netforce resisting separation of said mated coupling members.

In contrast to other coupling arrangements, rather than creating aseparation force or pressure balanced system, fluid pressure within thecoupling assembly is arranged to energise the assembly, providing a netforce resisting separation of the male and female coupling members. Bycontrol of the dimensions within the assembly, this net force (the “pullout” strength) can be set at a desired breakout strength, or setrelatively low, with the desired breakout strength set by an alternativemechanism.

Preferably the fluid passage connected to the first end of the femalecoupling member may be coincident with the through-bore of the femalemember and the fluid passage connected to the first end of the malecoupling member may be coincident with the through-bore of the malemember. The probe may comprise a second end of the male coupling member.The socket may comprise a second end of the female coupling member andthe through-bore of the female member may extend from the first end andintersect the socket.

Preferably the probe may be of substantially uniform outer diameter, andthe socket may be of substantially uniform inner diameter. Thethrough-bores in the male and female coupling members may besubstantially straight, wherein when the coupling members are mated inuse the through-bores define a straight fluid conduit. The through-boresin the male and female coupling members may be of identical constantdiameter.

Additionally the present invention provides a single in-line fluid flowbetween the two fluid passages, which enables the coupling to be‘pigged’.

Preferably the coupling assembly may further comprise releasableretaining means arranged to resist the uncoupling of the mated couplingmembers. The male coupling member may further include a diametricalthrough-hole and the female coupling member may further include at leastone diametrically aligned through-hole, and when mated the through holesmay be aligned and the retaining means may comprise a pin, which isinserted through the holes. The diametrical through-hole of the malecoupling member may be arranged on the probe and the or each diametricalthrough-hole of the female coupling member may be arranged in thesocket. The retaining means may comprise a first part, which, in use, isarranged fast with the male coupling member, and a second part, which,in use, is arranged fast with the female coupling member, and wherein inuse the first part and second part engage with each other, saidengagement comprising the retaining means. The first and second partsmay each comprise a rack of radial teeth. The radial teeth of the firstpart may face outwardly and the radial teeth of the second part may faceinwardly. The radial teeth of the first part may face inwardly, and theradial teeth of the second part may face outwardly.

Preferably, the first part comprises a clip. The clip may compriseresilient material. The clip may comprise first and second sectionsarranged about opposing sides of the first longitudinal axis and arejoined by a connecting section that in use abuts a flange on the malecoupling member, where said abutment comprises the first arrangement ofthe clip and male member, and wherein at least one of said first andsecond sections includes spaced from the connecting section the radialteeth. The radial teeth of the clip may be removeably engaged bypivoting at least one of the first or second sections about theconnecting section. The face of the flange in abutment with theconnecting section may comprise an oblique face.

Preferably the socket of the female coupling member further includes aclosed end and an aperture from the socket, wherein, in use, theaperture is arranged in communication with a space between the closedend and a distal end of the probe, such that when the probe is insertedinto the socket ambient fluid within the socket is forced out of theaperture and the egress rate of the ambient fluid from the aperturedetermines the insertion force required to insert the probe into thesocket. The aperture may extend through the closed end of the socket.The aperture may comprise a split pin which is inserted through a hole,the female coupling member further comprising the hole, which extendsorthogonal to the axis of the socket. The probe may further include anon-symmetrical feature that is arranged, in use, to co-operate with thesplit pin, such that when the probe is in an incorrect orientation aboutthe second longitudinal axis, the probe abuts the split pin before thethrough-bores are aligned.

Preferably the male and female coupling members further compriseco-operating alignment features wherein said co-operation limits therelative orientation about the second longitudinal axis that the probecan be inserted into the socket. The co-operating parts may comprise atleast one and preferably two male features which are fast to the malecoupling member and parallel to the second longitudinal axis, theco-operating parts may further comprise for each male feature acorresponding female feature, which are fast to the female couplingmember, wherein, during insertion of the probe into the socket, the oreach male feature co-operates with the or each female feature. The malefeatures may further comprise notches and the female coupling member mayfurther comprise apertures that intersect the female features, andwherein a locking means locates in the apertures and, when arranged inuse, engages with the notches to provide the releasable retaining means.

Preferably the male coupling member may comprise a valve, which preventsfluid flow along the through-bore in a closed position and allows fluidflow along the through-bore in an open position. The valve of the malecoupling member may be operable between the open and closed position byrotating an operable feature. The operable feature may be operated by apart of the female coupling member, such that the valve is rotated fromthe open position to the closed position when the probe is uncoupledfrom the socket. The valve may further comprise biasing means, whichacts to bias the valve towards the closed positions, wherein theoperable feature is operated by a part of the female coupling membersuch that the valve is moved towards the open position when the probe isinserted into the socket. Preferably the female coupling membercomprises a valve, which prevents fluid flow along the through-bore in aclosed position and allows fluid flow along the through-bore in an openposition. The valve of the female coupling member may be operablebetween the open and closed position by rotating an operable feature.The operable feature may be operated by a part of the male couplingmember, such that the valve is rotated from the open position to theclosed position when the probe is uncoupled from the socket. The valvemay further comprise biasing means, which acts to bias the valve towardsthe closed position, wherein the operable feature is operated by a partof the male coupling member such that the valve is moved towards theopen position when the probe is inserted into the socket.

Preferably the operable members include a first and second opposing edgeand the other coupling member includes a co-operating feature, whereinduring coupling the cooperating feature moves relative to the operablemember and along the second longitudinal axis, the co-operating memberabutting the first opposing edge to open the valve during coupling ofthe members and the co-operating member abutting the second opposingedge to close the valve during de-coupling of the members.

Preferably the male and female coupling members each include arespective through-bore closing member. The closing member of the malemember may be moveable between a closed position, in which the closingmember extends across the fluid aperture and wherein the second annularsealing ring is arranged on one side of the fluid aperture and a furthersealing ring is arranged on an opposing side of the fluid aperture, andan open position in which the closing member does not extend across thefluid aperture. The closing member of the female member may be moveablebetween a closed position, in which the closing member extends acrossthe fluid aperture and wherein the first annular sealing ring isarranged on one side of the fluid aperture and a further sealing ring isarranged on an opposing side of the fluid aperture, and an open positionin which the closing member does not extend across the fluid aperture.The closing members may be slidably mounted about the probe and withinthe socket respectively. The closing members may be biased toward theclosed position. Preferably the male and female coupling members mayeach include a retaining member for retaining each closing member in theclosed position, wherein, in the closed position, each coupling membercomprises a flat end.

Preferably the male coupling member is fabricated from a fibre compositestructure, wherein, along the probe, the fibre packing in the axialdirection is greater than the fibre packing in the radial direction. Thefemale coupling member may be fabricated from a composite structure,wherein, along the socket section, the fibre packing in the radialdirection is greater than the fibre packing in the axial direction.

According to a further aspect of the present invention, a method ofreleasably interconnecting fluid passages comprises inserting a probe ofa male coupling member into a corresponding socket of a female couplingmember, the coupling members being connected to the end of the fluidpassages and at the junction between the two fluid passages, eachcoupling member including a first end arranged for connection to thefluid passage and a through bore extending from the first end, whereinwhen mated in use, the through-bores of each coupling member arecoincident along a first longitudinal axis and the probe and socket arecoincident along a second longitudinal axis, which is inclined to thefirst axis, the through-bores providing a fluid conduit between the twofluid passages and fluid being substantially retained in the conduit bysealing means.

Preferably, the method further comprises inserting a breakout pinthrough diametrically aligned holes in the male and female couplingmembers.

The present invention includes any combination of the herein referred tofeatures or limitations.

The present invention can be carried into practice in various ways butseveral embodiments will now be described, by way of example, withreference to the accompanying drawings, in which:—

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic cross-sectional view of a first embodiment of thepresent invention in an unmated position;

FIG. 2 is a schematic cross-sectional view of the first embodiment ofthe present invention in a mated position;

FIG. 3 is a schematic cross-sectional view of a second embodiment of thepresent invention in an unmated position;

FIG. 4 is a schematic cross-sectional view of the second embodiment ofthe present invention in a mated position, wherein the position isunsecured.

FIG. 5 is a schematic cross-sectional view of the second embodiment ofthe present invention in the mated position, wherein the position issecured.

FIG. 6 is a schematic cross-sectional view of a third embodiment of thepresent invention in a mated position, wherein the position is secured.

FIG. 7 is a view of a forth embodiment of the present invention in anunmated position showing a male coupling member in a side view and afemale coupling member in a schematic-cross sectional view.

FIG. 8 is a schematic cross-sectional view of the forth embodiment ofthe present invention in a mated position, wherein the male couplingmember is not shown in a cross-sectional plane.

FIG. 9 is a schematic plan view of a fifth embodiment of the presentinvention in an unmated position.

FIG. 10 is a schematic cross-sectional view of the fifth embodiment ofthe present invention along A-A of FIG. 9.

FIG. 11 is a schematic cross-sectional view of the fifth embodiment ofthe present invention along line A-A of FIG. 9 when in an initial matingposition.

FIG. 12 is a schematic cross-sectional view of the fifth embodiment ofthe present invention along line A-A of FIG. 9 when in a mated position.

FIG. 13 is a side view of a sixth embodiment of the present invention ina mated position.

FIG. 14 is a side view of the sixth embodiment of the present inventionin a mid-coupled position.

FIG. 15 is a cross-sectional side view of the sixth embodiment of thepresent invention in the mated position.

FIG. 16 is a cross-sectional side view of the sixth embodiment of thepresent invention in the mid-coupled position.

FIG. 17 is a cross-sectional side view of a seventh embodiment of thepresent invention in an unmated position.

FIG. 18 is a cross-sectional side view of the seventh embodiment in anear-mated position.

FIG. 19 is a cross-sectional side view of the seventh embodiment in amated position.

FIG. 20 is a cross-sectional side view of an eighth embodiment of thepresent invention in an unmated position.

FIG. 21 is a cross-sectional side view of the eighth embodiment in amated position.

FIG. 22 is a side elevation view of a ninth embodiment of the presentinvention in an unmated position.

FIG. 23 is a side elevation view of the ninth embodiment in a near-matedposition.

FIG. 24 is a side elevation view of the ninth embodiment in a matedposition.

FIG. 25 a is a schematic cross-sectional side view of a tenth embodimentof the present invention in a mated position.

FIG. 25 b is an end view of FIG. 25 a.

FIG. 26 a is a schematic cross-sectional side view of the tenthembodiment in an un-mated position.

FIG. 26 b is an end view of FIG. 26 a.

FIG. 27 is a schematic cross-sectional side view of an eleventhembodiment of the present invention in an un-mated position.

FIG. 28 is a schematic cross-sectional side view of the eleventhembodiment in a near-mated position.

FIG. 29 is a schematic cross-sectional side view of the eleventhembodiment in a mated position.

FIG. 30 is a side elevation view of a twelfth embodiment of the presentinvention in an un-mated position.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT AND BEST MODE

FIGS. 1 and 2 illustrate a first embodiment of the present invention.The coupling assembly 101 comprises male coupling member 102 and femalecoupling member 103 and these are shown uncoupled and coupled together,in FIGS. 1 and 2 respectively. In this embodiment there is a couplingaxis A (the longitudinal axis along which the male coupling member 102is inserted into the female coupling member 103 to define a conduit forfluid flow) and a flow axis B, defined by that conduit. Axes A and Bsubtend an angle α of about 20°.

The male coupling member 102 includes a proximal region 104 and a distalregion in the form of a probe 106. The probe is in the form of asubstantially cylindrical rod, which has an axis coincident with thecoupling axis A. The male coupling member further comprises a circularlycylindrical through-bore 108, which has a straight axis that iscoincident with the flow axis B and extends between a first aperture andsecond aperture. Said through-bore comprising a substantially constantdiameter. The distal end of the proximal region includes the firstaperture of the through-bore 108 and is adapted to communicate with afirst fluid passage (not shown). The second aperture of the through-boreis arranged on a circumferential face of the probe.

The male coupling member 102 further includes a stop member 110, whichextends around its proximal region 104. The stop member 110 has afrontal abutment face 112, substantially at the junction between theprobe and the proximal region.

The through-bore 108 is defined by sidewalls 114, which are ofsubstantially uniform thickness and sufficient to withstand the forcesexerted by pressure of the fluid along the through-bore. As will beherein described, in use, the coupling assembly generates bendingforces. The thickness of the sidewall in the region of the frontalabutment face 112 assists in resisting such bending forces.

The male coupling member 102 further comprises an external, annularsealing ring 115 close to the free end of the probe. The sealing ring115 is seated within an annular groove, which extends circumferentiallyabout the outside of the probe. The external diameter of the sealingring is greater than the external diameter of the probe 106 in orderthat the sealing ring ensures a seal when the probe is inserted into thefemale coupling member 103.

A small diametrical through-hole 117 is provided in the probe closelyadjacent to its distal end.

The male coupling member may be fabricated by any well-knownmanufacturing method, for example casting or machining from a block.Alternatively, it is preferable to machine the male member from a rodwith the axis of the proximal end and probe coincident and excluding thethrough-bore. The rod can then be bent so that the axis of the proximalend and probe are inclined at the angle α before the through-bore ismachined.

The female coupling member 103 comprises a body that includes athrough-bore 121, which is of the same internal diameter as thethrough-bore 108 of the male coupling member 102, and a socket 122. Thethrough-bore 121 and the socket 122 are both substantially circularlycylindrical and straight. An open-end region 124 of the female couplingmember 103, which includes an aperture of the through-bore 121, isadapted to communicate with a second fluid passage (not shown). The axisof the socket 122 is coincident with the coupling axis A. The socket 122is of size to snugly receive the probe of the male member 102.

The socket 122 comprises a closed bore that extends up to an end face126. Disposed around the inside circumference of the socket, adjacent toits opening, is an internal, annular sealing ring 128. The annularsealing ring 128 is seated within an annular groove on the inside of thesocket 122. The internal diameter of the sealing ring is less than theinternal diameter of the bore of the socket such that, when the probe106 is inserted into the socket 122, the sealing ring 128 ensures a sealwith the cylindrical outer surface of the probe.

The end face 126 has a fluid egress aperture 130, whereby the socket isin communication with the ambient environment surrounding the femalecoupling member 103.

The through-bore 121 extends between the open-end region 124 and anaperture 132 in the circumferential wall of the socket 122. The aperture132 is located between the internal annular sealing ring 128 and closedend of the socket.

The open-end region 124 is comprised of a substantially cylindrical rodthat extends from the body of the female coupling member 103 and isco-axially aligned with the through-bore 121. In the open-end region124, sidewalls 134 define the through-bore. The sidewalls 134 are ofsubstantially uniform thickness and sufficient to withstand the forcesexerted by pressure of the internal fluid.

The body of the female member 103 is such that, during use, all thewalls are of sufficient thickness to withstand the forces exerted and inparticular the herein described bending forces acting to straighten thesocket and through-bore to lesser angles of interconnection.

A pair of small diametrically aligned through-holes 36 are provided inthe walls of the socket adjacent to its distal end.

The female coupling member may be fabricated by any well-knownmanufacturing method, for example casting or machining from a block.Alternatively, it is preferable to fabricate the female member from twoparts. A first part, which is machined from a rod and includes all thefeatures that are radial and axial to the axis of the socket, and asecond part comprising a rod or tube, which is attached to the firstpart. The axis of the second part is inclined to the first part and atthe angle α. The second part may be joined by any well-known method thatcreates a sealed joint between the two parts. The through-bore can thenbe machined.

To effect coupling, the male and female coupling members are moved intothe positions shown in FIG. 1, the probe 106 is then advanced along itsaxis (axis A), into the socket 122. During insertion the externalannular sealing ring 115, located around the cylindrical externalsurface of the probe, is able to pass the internal annular sealing ring128 located around the cylindrical internal surface of the socket as atleast one ring, and generally both, is composed of a resilientelastomeric material.

When the probe is fully inserted into the socket 22 along coupling axisA, the abutment of the stop member 110 against the female couplingmember 103 terminates the movement. In this position the through-bore108 of the male coupling member is brought into coincidence with thethrough-bore 121 of the female coupling member i.e. they are alignedalong flow axis B. As noted above these through-bores are of identicalinternal diameter, and when they are thus brought together they define asmooth, straight flow passage (see FIG. 2).

The fluid egress aperture 130 assists the insertion of the probe 6 intothe socket 122. Before inserting the probe 106 into the socket 122, thesocket contains the fluid of the ambient environment, for example air orseawater. As the probe is inserted into the socket the external sealingring 115 forms a seal with the walls of the socket. Consequently ambientfluid is forced in the direction of the probe's movement, relative tothe socket. A small amount of the ambient fluid contained within thesocket may escape down the through-bore 124 of the female couplingmember. However, once the sealing ring 16 passes the aperture 132 of thethrough-bore, the fluid can only exit from the socket through the egressaperture 130. It should be clear that the dimensions of the egressaperture 130 therefore determine the resistance force that arises oninsertion of the probe 106.

In use, fluid, for example oil, water or a water-based liquid, flowsthrough a conduit in the coupling assembly 101 under pressure. Theconduit allows fluid to flow between the two fluid passages andsubstantially through the through-bores 108, 121 of the male and femalecoupling members 102, 103. However, at the intersection between the twobores and because the external diameter of the probe is less than theinternal diameter of the socket, which is necessary in order to insertthe probe into the socket, there is also fluid in the annular spacebetween the probe and the socket. The external annular sealing ring 115,which forms a seal between the probe and the walls of the socket,prevents the fluid from escaping towards the closed end of the socket.The internal annular sealing ring 128, which forms a seal between thesocket and the radial surface of the probe, prevents the fluid fromescaping towards the open end of the socket. The fluid conduit thereforecomprises the two through bores 108, 121 and the annular space delimitedby the two sealing rings 115, 128.

The pressure of the fluid exerts an equal pressure on all the internalsurfaces of the conduit. The fluid pressure creates the bending forceswithin the coupling assembly, which act to lessen the interconnectionangle between axis A and B. The fluid pressure creates both separationforces and coupling forces. Thus, if the female coupling member is heldstationary, the separation force is the product of the fluid pressureand the cross sectional area of the probe 106 at the internal sealingring 128 and the coupling force is the product of the fluid pressure andthe cross sectional area of the probe 106 at the external sealing ring115. In the present embodiment, the arrangement of the seals is suchthat the coupling and separation forces create a net force that acts tourge or maintain the probe into the socket. Said net force thereforebeing a product of the fluid pressure and the cross sectional area ofthe annular space between the probe and the socket. It will be readilyapparent that by arranging both the annular sealing rings either aboutthe probe or about the socket, a zero net coupling force is achieved.

When the male and female coupling members are coupled together as shownin FIG. 2 the holes 117, 136 in those members are aligned with eachother. A pin may be inserted through them, to help maintain the male andfemale members in coupled relationship. This helps to maintain thecoupling when a separation force is inadvertently applied. On the otherhand when a very large force is applied, that could if resisted lead todamage of the coupling assembly, the pin can fail and the male andfemale members separate. The force at which this occurs being thebreakout force.

With reference to FIG. 3 and according to a second embodiment of thepresent invention, a coupling assembly 201 comprises at least one malecoupling member 202 and a manifold 203. Each male coupling member isgenerally in accordance with the male coupling member of the previousembodiments and includes: a proximal region 204 arranged forcommunication with a first fluid passage (not shown); a probe 206, whichis arranged coincident with a coupling axis A; a through-bore 208, whichhas an axis coincident with the flow axis B and extends between a firstaperture on a distal end of the proximal region and a second aperture ona circumferential face of the probe; and an external sealing ring 215,which is arranged close to the free end of the probe.

According to the second embodiment each male coupling member furthercomprises a radial flange 216, a mechanical clip 217, and an alignmentfeature 210. The radial flange extends about the proximal region andincludes upper and lower surfaces that are orthogonal to the flow axisB. A circumferential sidewall connects the upper and lower surfaces andis tapered towards the lower surface.

The mechanical clip 217 comprises a circular disc section 218 and twoside sections 219, 220. The circular disc section comprises upper andlower faces and includes a central hole, thus resembling a washer. Thetwo side sections are substantially identical and each is substantiallypart tubular in form. Each side section subtends an angle ofapproximately 90° about the disc section. The side sections extendaxially from either side of the lower face of the disc section and fromthe outermost regions of the disc. The side sections and the adjoiningdisc section comprise substantially one part, which is formed from aresilient plastics material.

Each side section includes engaging means 219 a, 220 a. The engagingmeans comprise a rack of circumferential teeth of generally saw toothform and are located on an outside aspect and close to the free end ofeach side section. In each rack of teeth, each tooth has a face that isorthogonal to the flow axis and a face that is oblique to the flow axis.

In use, the disc section of the clip locates about the proximal sectionand orthogonal to the flow axis, wherein the clip can slidelongitudinally along the flow axis but is delimited towards the probe byabutment between the lower face of the disc and the upper face of theflange.

The distal end of each probe includes the alignment feature 210. Thealignment feature comprises a flattened portion of the wall about theend region of the probe. The alignment feature further comprises aradial face and an axial face. As will be herein described the alignmentfeature ensures the correct alignment of the male coupling member and sois not symmetrical.

The manifold 203 includes at least one and preferably a plurality (notshown) of connection sites to correspond to each male coupling member.Each connection site contains features that are generally in accordancewith the female coupling member of the previous embodiments and include:a through-bore 221, which is coincident with the flow axis B and extendsfrom a first end that is arranged for communication with a second fluidpassage (not shown); a socket 222 that is coincident with the couplingaxis A; and an internal sealing ring 228, which is arranged close to theopen end of the socket.

According to the second embodiment, each coupling site further includesa split pin 230 and engaging means comprising internal, radial teeth236. The split pin 230 is housed in a circular hole that extends throughthe manifold and between the closed end region of the socket and theambient environment. The circular hole is arranged orthogonal to thecoupling axis A and at the edge of the socket. The split pin is housedfast in the hole. The pin is split so that fluid may enter the centre ofthe pin, thus creating a fluid egress path between the bottom of thesocket and the ambient environment and operating generally in accordancewith the fluid egress aperture of the previous embodiments.

The internal, radial teeth 236 comprise an axis that is coincident withthe axis of the through-bore 221. The teeth are of general saw toothform to correspond with the engaging means 219 a, 220 a of themechanical clip.

The coupling assembly of the second embodiment is shown in the unmatedposition in FIG. 3. The male member is inserted into the socket of themanifold by relative movement along the coupling axis A. The probe isinserted until the probe abuts the split pin 230. As shown in FIG. 4,when the probe is correctly orientated, the axial face of the alignmentfeature passes the split pin, wherein said abutment occurs with theradial face of the alignment feature. When the probe is in the correctorientation the pin is arranged to delimit the relative movement whenthe through-bores in the male coupling member and the manifold arecoincident. If the male member is not correctly orientated said abutmentoccurs between the distal end of the probe and the pin. When the distalend of the probe abuts the pin, the axis of the through bores in themale coupling member and manifold respectively are not aligned.

In order to insert the male member to the position shown in FIG. 4, themechanical clip is moved axially along the flow axis B and away from theprobe. When the probe is correctly inserted the axis of the mechanicalclip is aligned with the axis of the internal, radial teeth 236 suchthat the mechanical clip can be slid axially along the flow axis B andtowards the manifold. The two side sections of the mechanical clip, flexinwardly due to the resilient nature of the clip thus allowing theengaging means 219 a, 220 a to engage with the internal, radial teeth ofthe manifold. The clip is shown fully mated in FIG. 5, wherein the teethof the clip and manifold engage. Said engagement resists relativemovement between the clip and manifold away from each other.Furthermore, abutment between the clip and the radial flange of the malecoupling member gives the coupling assembly breakout strength.

In use the coupling assembly works generally in accordance with theprevious embodiments. If the breakout force is exceeded then the teethof the mechanical clip are designed to shear such that the couplingcomes apart. Alternatively, to uncouple the assembly in a controlledmanner, the free end of the side sections of the mechanical clip can beforced toward each other such that the teeth are removed from engagementand the clip slid away from the manifold.

According to the third embodiment of the present invention and as shownin FIG. 6, the coupling assembly comprises a male coupling member 302and female coupling member 303. The male coupling member is generally inaccordance with the male coupling member of the second embodiment andcomprises a proximal region 304 arranged for communication with a firstfluid passage (not shown); a probe 306, which is arranged coincidentwith a coupling axis A; a through-bore 308, which has an axis coincidentwith the flow axis B and extends between a first aperture on a distalend of the proximal region and a second aperture on a circumferentialface of the probe; an external sealing ring 315, which is arranged closeto the free end of the probe; a radial flange 316, which extendsradially from the proximal region; an alignment feature 310, which isformed in the distal end of the probe; and a mechanical clip 317, whichis slidably mounted about the proximal region of the male member.

The mechanical clip of the third embodiment comprises a circular discsection 318 and two side sections 319, 320. The side sections differfrom that described in the second embodiment in that the circular discsection joins the two side sections at a mid section rather than attheir ends. The side sections therefore having a first end that extendsfrom one side of the circular disc section and a second end that extendsfrom the opposite side. The side sections differ further from thatdescribed in the second embodiment, in that the engaging means 319 a,320 a comprising a rack of circumferential teeth of generally saw toothform are located on an inside aspect of the side sections rather thanthe outside aspect. The engaging means are located on the first end ofthe side sections.

The radial flange 316 differs from that described in the secondembodiment in that it comprises a lower face, which is orthogonal to theaxis of the coupling assembly, and an oblique upper face.

The female coupling member is generally in accordance with the femalecoupling member of the first embodiment and comprises: a through-bore321, which is coincident with the flow axis B and extends from a firstend that is arranged for communication with a second fluid passage (notshown); a socket 322 that is coincident with the coupling axis A; and aninternal sealing ring 328, which is arranged close to the open end ofthe socket. The female member further comprises a split pin 330generally in accordance with the split pin described in the secondembodiment, which is arranged in the socket, and engaging means, whichdiffers from the engaging means described in the second embodiment inthat the engaging means comprises external, radial teeth 336.

The external, radial teeth 336 comprise an axis that is coincident withthe axis of the through bore 321. The teeth are of generally saw toothform to correspond with the engaging means 319 a, 320 a of themechanical clip.

The coupling assembly of the third embodiment is mated substantially asdescribed in the mating of the second embodiment. The teeth of themechanical clip engage with the rack of teeth on the female member byflexing outwardly. When engaged, the teeth inhibit relative movementbetween the clip and female coupling member in an uncoupling direction.Abutment between a lower face of the circular section comprising theclip and the oblique upper face of the flange inhibits decoupling of thecoupling members. In use, the clip therefore provides breakout strength.

If the breakout strength is exceeded, the teeth of the clip are designedto shear, thus allowing the probe to be unmated. The breakout strengthis enhanced due to the geometry of the oblique upper face of flange 326resulting in the side sections bending inwardly as the male and femalemembers are pulled apart. The clip may be removed deliberately bysqueezing the second ends of the side sections inwardly such that thefirst ends are forced outwardly and away from engagement with the radialteeth.

According to a fourth embodiment and as shown in FIGS. 7 and 8, acoupling assembly comprises male and female coupling members. The malecoupling member 402 is generally in accordance with the male couplingmember of the previous embodiments and comprises: a proximal region 404arranged for communication with a first fluid passage (not shown); aprobe 406, which is arranged coincident with a coupling axis A; athrough-bore 408, which has an axis coincident with the flow axis B andextends between a first aperture on a distal end of the proximal regionand a second aperture on a circumferential face of the probe; and anexternal sealing ring 415, which is arranged close to the free end ofthe probe.

The probe of the male coupling member is substantially less elongatethen previous embodiments and extends minimally from the proximal regionsufficient only so that the external outer sealing ring can be seatedbetween the distal end of the probe and the aperture of the throughbore. Furthermore, the distal end of the probe is in a plane that isparallel to the flow axis B, rather than radial to the coupling axis Aas shown in the previous embodiments. The external annular sealing ring415 is also arranged in a plane parallel to the flow axis B, rather thanradial to the coupling axis A as previously described.

The male coupling member further comprises a plate 417. The plateextends radially from the proximal region and includes a hole 418. Thehole extends through the plate and is arranged such that the axis of thehole is orthogonal to the flow axis B.

The female coupling member is generally in accordance with the femalecoupling assembly of the previous embodiment and comprises; athrough-bore 421, which is coincident with the flow axis B and extendsfrom a first end that is arranged for communication with a second fluidpassage (not shown); a socket 422 that is coincident with the couplingaxis A; and an internal sealing ring 428, which is arranged close to theopen end of the socket.

The socket of the female coupling member is substantially less elongatethan that described in previous embodiments and corresponds with thesize of the probe. The female coupling member further comprises a plate436 that extends axially from the aperture of the socket. The plateincludes a hole 437 that extends through the plate and which has an axisorthogonal to the flow axis B of the through bore within the femalemember.

When mated in use, the external annular sealing ring 415 creates a sealbetween the socket and probe that lies in a plane parallel to the flowaxis B and spaced outwardly from the extent of the through bores 421,408. Furthermore, when mated in use, the plates 417, 436 are arrangedwith part of their free ends overlapping each other such that the holes417, 436 are aligned. A pin (not shown) can be inserted through theholes to provide breakout strength to the coupling. Said pin operatinggenerally in accordance with the pin described in the first embodiment.

The coupling assembly operates, in use, substantially as hereindescribed in the previous embodiments. The advantage of the fourthembodiment is that the coupling assembly retains a mainly cylindricalprofile such that the coupling assembly may be arranged inside a secondpipe or fluid conduit.

According to a fifth embodiment of the present invention and withreference to FIGS. 9-12, a coupling assembly comprises male and femalecoupling members. The male coupling member is generally in accordancewith the male coupling member of the previous embodiments and comprises:a proximal region 504 arranged for communication with a first fluidpassage (not shown); a probe 506, which is arranged coincident with acoupling axis A; a through-bore 508, which has an axis coincident withthe flow axis B and extends between a first aperture on a distal end ofthe proximal region and a second aperture on a circumferential face ofthe probe; and an external sealing ring 515, which is arranged close tothe free end of the probe.

The male coupling member further comprises first 540 and second 541coupling arms which are arranged on opposite sides of the probe. Eachcoupling arm extends from a side aspect of the proximal section. Eacharm is substantially circular and comprises a corresponding axis that isaligned parallel to the coupling axis A. A free end of each arm includesa plurality of notches 543 that are arranged spaced apart and along theaxis of the arm. The or each notch contains a first and second face. Thefirst face is spaced nearest the free end and is orthogonal to the axisof the arm. The second face is oblique to the axis, such that a V-shapeis formed. The region of the arm extending from the proximal section isfrusto-conical in shape and arranged so that it tapers towards the freeend of the arm. A second region of the arm extending between thefrusto-conical region and the free end is substantially circularlycylindrical.

The female coupling member is generally in accordance with the femalecoupling member of previous embodiments and comprises: a through-bore521, which is coincident with the flow axis B and extends from a firstend that is arranged for communication with a second fluid passage (notshown); a socket 522 that is coincident with the coupling axis A; and aninternal sealing ring 528, which is arranged close to the open end ofthe socket.

The female coupling member is substantially wider than that described inprevious embodiments and further includes a first 550 and second 551alignment holes. The alignment holes are arranged on either side of thesocket and are substantially cylindrical. Each of the alignment holes551 extend parallel to the coupling axis A and in a plane to the socket.The end region extending from a face containing the open end of thesocket is frusto-conical such that the aligned hole tapers away from theface. A second region of the alignment holes is substantially circularlycylindrical and extends between the frusto-conical section and a facecontaining an aperture of a fluid egress aperture 530, the fluid egressaperture being generally in accordance with the fluid egress aperturedescribed in the first embodiment. Since the alignment hoes are parallelwith the socket they are not intersected by the socket or through-bore.

The female coupling member further comprises a locking means 554. Thelocking means comprises a first and second pin which are spaced fromeach other and joined by a plate at their distal ends. The pins 555extend from the plate in a common plane. The free end of each pin isangled to form an oblique end face. The pins of the locking means areinserted into two holes formed in the female member. The holes arearranged either side of the through-bore and socket. Said holes furtherbeing arranged such that they intersect each alignment holerespectively. Said holes extending upwardly from the intersection withthe alignment holes and an outer surface of the female coupling member.

The weight of the locking means biases the pins 555 downwardly, thuswhen uncoupled, as shown in FIG. 10, the pins abut the internal boundaryof the alignment holes.

The alignment pins ensure that the male coupling member is correctlyoriented so that the two through-bores are aligned and form a straightfluid flow. The probe is inserted into the socket by relative movementalong the coupling axis A. As shown in FIG. 11, the alignment pinsinitially engage with the frusto-conical region of the alignment holesin the female coupling member. This reduces the tolerance of theoriginal rotational alignment. As the probe is further inserted into thesocket the alignment arms engage in sliding contact with the alignmentholes.

As the alignment arms reach the intersection of the pins 555 with thealignment holes, the alignment arms abut the oblique end face of thepins and through further relative movement forces the pins upwardly andout of the alignment holes. When the coupling members are mated in use,a stop member of the male coupling member, which is generally inaccordance with the stop member described in the first embodiment, abutsthe face of the female coupling member. At this point, the pins of thelocking means are aligned with the notches in the alignment arms. Underthe weight of the locking means the pins therefore engage with thenotches.

Each pin 555 of the locking means provide breakout strength to theassembly. The probe is inhibited from being removed from the socket byabutment of the pins and orthogonal ends of the notches. If the breakoutforce is exceeded, the tips of the pins are designed to fail such thatthe probe can be removed from the socket.

According to the sixth embodiment and with reference to FIG. 13-16, acoupling assembly comprises a male 602 and female 603 coupling members.

The male coupling member is generally in accordance with the malecoupling member of previous embodiments and comprises: a proximal region604 arranged for communication with a first fluid passage (not shown); aprobe 606, which is arranged coincident with a coupling axis A; athrough-bore 608, which has an axis coincident with the flow axis B andextends between a first aperture on a distal end of the proximal regionand a second aperture on a circumferential face of the probe; and anexternal sealing ring 615, which is arranged close to the free end ofthe probe.

The male coupling member further comprises a valve, an arm 660 and fluidrelease means. The valve 662 comprises any well-known valve and inparticular, although by no means limited to, a ball valve, which isrotatable between an open position and a closed position. The valve ishoused in the proximal region of the probe and is arranged orthogonal tothe flow axis B. The valve intersects the axis of the through-bore suchthat in the open position the valve creates a straight fluid conduit inaccordance with previous embodiments. Sealing means 664 ensures fluidcannot escape the through-bores via the valve. The valve is closed byrotating the valve through 90°.

The valve further comprises a plate 668 that is held fast to the top ofthe valve and on the outside of the coupling member. The plate includesa first straight edge and a rounded distal end. Wherein, in use and inthe closed position, the first edge is arranged parallel to the couplingaxis A.

The arm 660 comprises a first section that is arranged parallel with theflow axis and a second section that is arranged at 90° to the firstsection. The arm extends from the outside of the proximal region.

The fluid release means comprises a fluid conduit that extends betweenthe distal end of the probe and an aperture on the side face of theprobe. The fluid conduit comprises a small diameter hole 670 thatextends from the aperture on the side of the probe and orthogonal to theprobe axis. The small diameter hole connects to a large diameter recess671 that extends along the axis of the probe and from the distal end inorder to reduce the weight of the probe. The small diameter hole isarranged on the probe between its distal end and the external annularsealing ring 616. A further annular sealing ring 671 is arranged aboutthe probe and between the distal end of the probe and the small diameterhole. When mated in use, the external annular sealing ring 616 andfurther annular sealing ring 671 seal the probe with the socket.

The female coupling member is generally in accordance with the femalecoupling members of previous embodiments and comprises: a through-bore621, which is coincident with the flow axis B and extends from a firstend that is arranged for communication with a second fluid passage (notshown); a socket 622 that is coincident with the coupling axis A; and aninternal sealing ring 628, which is arranged close to the open end ofthe socket.

The female coupling member further comprises a valve 690 and an arm 680.The valve 690 is the same as the valve of the male coupling member andis arranged between the first fluid conduit and the intersection of thethrough-bore and socket. The arm 680 comprises a first section, which isarranged parallel to the flow axis B and extends from the outside of thesocket, and a second section which is arranged at 90° to the firstsection.

When uncoupled, the valves of the male and female coupling members arein the closed position such that fluid cannot escape from the ends ofthe coupling members. As the probe is inserted into the socket the freeend of each of the arms slides along the first edge of each plate on thetop of the respective valves. During insertion the valves are notrotated and remain in the closed position. Once inserted in use,rotating the plates such that the first edge of each plate moves towardthe second region of each respective arm opens the valves. For example,the plate of the valve on the male member moves towards the secondregion of the arm on the female member. The rotation of the valves isdelimited in the open position by abutment of the plates and arms.

When decoupling, relative movement between the coupling members causeseach arm to rotate the respective plates towards the closed position.Decoupling of the coupling members continues the relative movement andtherefore the closing rotation of the valves, such that the valves arein the closed position when the aperture of the fluid release becomesconnected to the through-bore of the female member and immediatelybefore the through-bore of the male member passes the internal annualsealing ring. When said position is reached the fluid trapped in thethrough-bores and between the closed valves can escape through the fluidrelease conduit and into the ambient environment. When the valves are inthe closed position the first edge of each plate is again alignedparallel with the coupling axis A such that the arms do not furtherrotate the valves.

The advantage of the sixth embodiment is that the ends of the couplingmembers are closed off before the through-bore of the male memberbecomes unsealed with the through-bore of the female member. Such anarrangement means that even under hot breaking conditions where thecoupling members are forced apart, fluid does not “spit” from the endsof the coupling members. Furthermore, under such uncoupling, thecoupling members are not forced apart by the pressure of the fluidegressing from the coupling members.

In a seventh embodiment, and with reference to FIGS. 17 to 19, acoupling assembly 701 comprises a male 702 and a female 703 couplingmember substantially in accordance with the first embodiment.

FIG. 17 shows the coupling assembly 701 uncoupled. In accordance withthe first embodiment, the male member 702 includes: a proximal region704 arranged for communication with a first fluid passage (not shown); aprobe 706, which is arranged coincident with a coupling axis A; athrough-bore 708, which has an axis coincident with the flow axis B andextends between a first aperture on a distal end of the proximal regionand a second aperture on a circumferential face of the probe; and anexternal sealing ring 715, which is arranged close to the free end ofthe probe.

The male coupling member 702 comprises a first inner part, whichcomprises the probe, and also a tube section 716 that extends from theprobe and is coincident to the flow axis B. The external diameter of thetube is less than the external diameter of the probe, such that a hip713 is formed at the intersection. The end of the tube section remotefrom the probe comprises the proximal region 704 that connects with thefirst fluid passage (not shown). The proximal region further comprises aradial groove within which a removable stop member 718 can be securedfast to the tube section.

The second part forms a sleeve 717 about the outside of the tube sectionof the inner part. The sleeve comprises a thick-walled hollow rod with athrough bore coincident with its axis. The through bore has a step 719,such that its internal diameter in the proximal region 704 is largerthan in its region adjacent to the probe. In the latter region the borefits snugly about the tube section. The step 719 is formed at 90° to theaxis B.

The sleeve is arranged about the tube by removing the stop member 718and sliding the sleeve onto the tube section. A spring 720 is alsoarranged about the tube. A first end of the spring abuts the stop member718 and a second end of the spring abuts the step 719 of the sleeve suchthat the sleeve is urged to abut the hip 713.

In accordance with the first embodiment, the female coupling member 703comprises: a through-bore 721, which is coincident with the flow axis Band extends from a first end that is arranged for communication with asecond fluid passage (not shown); a socket 722 that is coincident withthe coupling axis A; and an internal sealing ring 728, which is arrangedclose to the open end of the socket.

The female coupling member 703 further comprises a circular ordisc-shaped recess 740 formed in the face 723 of the coupling member,and forming the open end of the socket. The recess 740 is coincidentwith the flow axis B in the assembled device (FIG. 19) and is sizedappropriately so as to accommodate snugly the forward end of the sleeveof the male coupling member, as shown in FIG. 19.

The probe of the male coupling member can be inserted into the socket ofthe female coupling member until a near-mated position shown in FIG. 18is reached, where the sleeve abuts the face 723, but is not within therecess 740. To complete the insertion of the probe, the sleeve is urgedto slide toward the stop member 718, against the action of the spring720. As shown in FIG. 19, when the probe is inserted such that the twothrough bores are aligned, the sleeve can locate in the recess 740. Thespring keeps the sleeve within the recess and in abutment with the hip.

When coupled, as shown in FIG. 19, the probe is prevented from beingwithdrawn from the socket by engagement of the forward end of the sleevein the recess 740, aided by the spring 720. In order to break thecoupling apart unintentionally, for example by means of excess fluidpressure in the fluid passages or mechanical dislodgement, the corner742 of the female member would have to fracture from the couplingmember. Breakout strength is therefore provided. However intentionaluncoupling is achieved easily. Sleeve 717 is withdrawn from recess 740,against the spring force. The corner is thereby cleared; it is no longeran abutment obstructing the sleeve. The withdrawal movement may becontinued.

In an eighth embodiment and with reference to FIGS. 20 and 21, acoupling assembly 801 comprises male 802 and female 803 couplingmembers. The coupling assembly is substantially in accordance with thefirst embodiment except that the external sealing ring is replaced by asecond internal sealing ring 815 that creates a seal between a probe anda socket (as in the first embodiment), and the probe and socket has avarying diameter rather than a constant diameter.

The female coupling member is substantially in accordance with the firstembodiment and comprises a through-bore 821, which is coincident withthe flow axis B and extends from a first end that is arranged forcommunication with a second fluid passage (not shown); a socket 822 thatis coincident with the coupling axis A; and an internal sealing ring828, which is arranged close to the open end of the socket.

The male coupling member is substantially in accordance with the firstembodiment and includes a proximal region 804 arranged for communicationwith a first fluid passage (not shown); a probe 806, which is arrangedcoincident with a coupling axis A; and a—through-bore 808, which has anaxis coincident with the flow axis B and extends between a firstaperture on a distal end of the proximal region and a second aperture ona circumferential face of the probe.

The socket 822 includes a constant diameter section, between the first815 and second 828 internal sealing rings. However, immediately adjacentthe first sealing ring 815, towards the closed end of the socket, thediameter of the socket decreases; and immediately adjacent the secondsealing ring 828, towards the open end of the socket, the diameter ofthe socket increases. The profile of the probe matches that of thesocket such that, as seen in FIG. 21, when the coupling is mated theprobe fits snugly within the socket.

In use, the tapering of the respective socket and probe adjacent to thesealing rings prevents the sealing rings from being extruded out oftheir seatings due to the pressure of the fluid.

In a ninth embodiment, and with reference to FIGS. 22 to 24, a couplingassembly 901 comprises a male 902 and a female 903 coupling member,generally in accordance with the sixth embodiment.

FIG. 22 shows the coupling assembly uncoupled. The male coupling member902 includes: a proximal region 904 arranged for communication with afirst fluid passage (not shown); a probe 906, which is arrangedcoincident with a coupling axis A; a through-bore 908, which has an axiscoincident with the flow axis B and extends between a first aperture ona distal end of the proximal region and a second aperture on acircumferential face of the probe; an external sealing ring 915, whichis arranged close to the free end of the probe; and a valve 962 which isrotatable between a closed position (FIG. 22) and an open position (FIG.24).

The valve comprises a plate 968 that is held fast to the top of thevalve and on the outside of the coupling member. The outline perimeterof the plate includes a first edge that is substantially flat and anopposing second edge that is arcuate. When the valve is in the closedposition, the straight edge is arranged perpendicular to the flow axis Band the end of the arcuate edge furthest from the pivot point of theplate (the centre axis of the valve) is provided to the coupling axis A.The centre axis of the valve is arranged substantially in line with thestraight edge.

The male coupling member further comprises an arm 960 that extends fromthe distal end of the probe in line with axis A. A pin 961 extends fromthe end of the arm. The pin is parallel with the axis of the valve.

The female coupling member 903 includes: a through-bore 921, which iscoincident with the flow axis B and extends from a first end that isarranged for communication with a second fluid passage (not shown); asocket 922 that is coincident with the coupling axis A; an internalsealing ring 928 (not shown), which is arranged close to the open end ofthe socket; and a valve 990 such as any well known ball valve.

The valve is operated by a series of pivoted links. A first link 992 isattached fast to the valve. An intermediate link 993 is pivotablyattached to the first link at a location offset from the axis of thevalve. The opposite end of the intermediate link is pivotably attachedto an operable member 994. The operable member rotates about a pointthat is fixed with respect to the female member 903 and located on a barthat extends from the body of the female member. The intermediate linkis pivotably connected to the operable member offset from its axis ofrotation. The offset is the same as that between the offset between theintermediate link and axis of the valve, such that when the operablemember rotates so does the valve.

The operable member is substantially similar to the plate 968 of themale member and has a straight edge and opposing arcuate edge. When thevalve 990 is closed, as shown if FIG. 1, the straight edge is oblique tothe coupling axis and the end of the arcuate edge furthest from the axisof rotation is parallel to the coupling axis B.

The female member includes an arm 980 that extends from the outside ofthe body of the female member. A pin 981 extends from the distal end ofthe arm and parallel to the axis of the valves.

To couple the assembly, the probe is inserted into the socket along thecoupling axis until a first position, as shown in FIG. 23, in which thepins 981, 961 abut the straight edge of the plate 968 and operablemember 994 respectively. At this position the valves are still closed.As the probe is inserted further, the valves are opened until, when in asecond position as shown in FIG. 24, the through bores are aligned andthe valves opened.

The opening of the valves is substantially similar and will be describedherein with reference to valve 990 only. As the probe is insertedfurther, the pin moves in relation to the valve parallel to the couplingaxis. The pin therefore remains in abutment with the straight edge butmoves firstly toward the pivot point and then away as is necessary torotate the plate and consequently open the valve. During decoupling, thepin moves relative to the plate parallel to the coupling axis B. Atfirst the pin moves freely of the plate before abutting the opposingarcuate face. During further decoupling, the plate moves firstly towardthe pivot point and then away as is necessary to rotate the plate andconsequently close to the valve. When the valve is closed the pin movespast the end of the arcuate edge that is parallel to the coupling axis Aand the probe decoupled.

A significant advantage of the embodiment is that the coupling anddecoupling of the members opens and closes the valves respectivelywithout any further intervention.

In a tenth embodiment and with reference to FIGS. 25 to 26, a couplingassembly 1001 comprises a male 1002 and a female 1003 coupling member

As with the seventh embodiment, the male member 1002 comprises an innerpart and a sleeve 1017.

The inner part includes: a proximal region 1004 arranged forcommunication with a first fluid passage (not shown); a probe 1006,which is arranged coincident with a coupling axis A; a through-bore1008, which has an axis coincident with the flow axis B and extendsbetween a first aperture on a distal end of the proximal region and asecond aperture on a circumferential face of the probe; and an externalsealing ring 1015, which is arranged close to the free end of the probe.

The sleeve is slidably mounted about the proximal region of the firstpart and urged by spring 1020 towards the probe and abutment with a hip1013 formed at the intersection of the probe and proximal region.

As with the seventh embodiment, the female coupling member 1003comprises: a through-bore 1021 which is coincident with the flow axis Band extends from a first end that is arranged for communication with asecond fluid passage (not shown); a socket 1012 that is coincident withthe coupling axis A; an internal sealing ring 1028, which is arrangedclose to the open end of the socket; and a disk-shaped recess 1040,which is formed in an end face of the coupling member that forms theopen end of the socket.

The disk-shaped recess 1040 is defined by a semicircular protrusionintegrally formed with the female coupling member and an opposingsemicircular washer piece 1041. The semicircular washer piece isseparate to the female coupling member. The semicircular washer piece isarranged on the female coupling member and relative to the semicircularprotrusion such that they combine to form a circular ridge. The axis ofthe circular ridge is coincident with axis B. The centre of the circularridge forms the disk-shaped recess 1040 with the through-bore 1021 inthe centre. The washer piece 1041 is held to the semicircular protrusionon the coupling member by a retaining member 1042.

Retaining member 1042 comprises a spring or band type arrangementconsisting of a number of turns. The spring or band has a diametersubstantially the same as the diameter of the circular protrusion. Assuch, the spring or band fits snugly about the semicircular protrusionand the semicircular washer piece and thereby secures the semicircularwasher piece is firmly to the coupling member.

The male coupling member can be inserted into the socket of the femalecoupling member substantially as previously described with reference tothe seventh embodiment. During insertion to the fully coupled position,as shown in FIG. 25 a, the retaining spring or band and the washer piecedo not substantially move.

As previously described with reference to the seventh embodiment, in themated position, as shown in FIG. 25 a, the probe is prevented from beingwithdrawn from the socket by engagement between the sleeve and washerpiece. However, at a predetermined breakout force the retaining springexpands radially thereby allowing the washer piece to move radially awayfrom the fixed semicircular protrusion, which allows the male couplingmember to decouple. Due to the resilient nature of the retaining spring,after disengagement, the retaining spring returns to its original size.This resiliency thereby returns the washer piece back to its position inabutment with the semicircular protrusion. When the cause of thebreakout force has been removed, the probe may then be inserted into thesocket and the coupling re-coupled. The retaining spring therebyprovides breakout strength to the coupling.

Intentional de-coupling of the male and female coupling members can beeasily achieved by withdrawing the sleeve from the disk-shaped recess,as previously described with reference to the seventh embodiment.

The advantage of such an embodiment is that breakout strength isachieved without destructively damaging either of the male or femalecoupling members or any part thereof. The resilient nature of theretaining member also allows easy re-coupling after a breakout incident.

In an eleventh embodiment, and with reference to FIGS. 27 to 29, acoupling assembly 1101 comprises a male 1102 and a female 1103 couplingmember.

FIG. 27 shows the coupling assembly uncoupled. In accordance with thefirst embodiment, the male coupling member 1102 includes: a proximalregion 1104 arranged for communication with a first fluid passage (notshown); a probe 1106, which is arranged coincident with a coupling axisA; a through-bore 1108, which has an axis coincident with the flow axisB and extends between a first aperture on a distal end of the proximalregion and a second aperture on a circumferential short face of theprobe; and an external sealing ring 1115, which is arranged close to thefree end of the probe.

The male coupling member 1102 comprises a radial flange, which isarranged at the intersection of the proximal region and the probe andincludes a frontal abutment face and a circumferential face. A sheathmember 1107 is attached fast to the male coupling member and secured atthe circumferential face of the radial flange. The sheath member 1107comprises a substantially tubular section and extends parallel to thecoupling axis A. The sheath extends from the radial flange and towardsthe free end of the probe. The distal end of the probe and the distalend of the sheath terminate in the same plain. An internal radial flangeextends from the distal end of the sheath and towards the centre axis.

A semicircular hole 1119 is formed through the sheath and arranged atthe distal end region. The hole has a centre axis that is coincidentwith the flow axis B. As will become clear later, the hole is sized soas to accommodate the female coupling member.

On an opposing side of the sheath to the hole, an engaging featureextends parallel to the coupling axis A and from the distal end of thesheath. The engaging means 1166 comprises a plate with a through-holethat is perpendicular to the coupling axis A.

A closing member 1162, comprising a tubular section, is slidably mountedon the end of the probe. The closing member includes an externallyextending radial flange 1163 that is arranged off-set from one end ofthe closing member. The off-set corresponds to the thickness of theinternal radial flange of the sheath.

A biasing means such as a spring 1164 is arranged in the radial spacecreated between the sheath and probe. The spring acts at one end on thefrontal abutment face 1112 and on the other end acts on the externalradial flange of the closing member. The spring biases the closingmember to a closed position as shown in FIG. 27, wherein the closingmember is biased towards abutment between the external radial flange ofthe closing member and the internal radial flange of the sheath. In theclosed position the end of the sheath, closing member and probe form aflat face.

In the closed position the first external annular sealing ring 1115 islocated between the distal end of the probe and the aperturethrough-bore 1108 and acts to seal the probe to the closing member. Aninternal sealing ring 1165, housed within an internal annular recessformed in the closing member and positioned on the other side of theaperture of the through-bore 1108, also acts to seal the probe andsheath. The arrangement of the two sealing rings, 1115 and 1065, sealsfluid within the through-bore 1108.

As with the first embodiment, the female coupling member 1103 comprises:a through-bore 1121, which is coincident with the flow axis B andextends from a first end that is arranged for communication with asecond fluid passage (not shown); a socket 1122 that is coincident withthe coupling access A; and an internal sealing ring 1128, which isarranged close to the open end of the socket.

The female coupling member 1103 comprises an internal closing member1190 that operates within the socket 1122 and a retaining member 1191that retains the closing member within the socket.

The retaining member comprises a tubular section with a substantiallyclosed end. The retaining member is located within a hole formed throughthe closed end of the socket and is secured fast to the female member.The axis of the retaining member is coincident with coupling axis A. thediameter of the retaining member is less than the internal diameter ofthe socket, such that the retaining member extends within the socket andfrom the closed end to a midway position along the socket. Thesubstantially closed end of the retaining member is therefore locatedwithin the socket. A hole, coincident with the coupling axis A, isformed through the substantially closed end.

The closing member comprises a central rod section, which includes aradial flange that extends outwardly from one end. The other end isattached to a radial face of a closed end of a tube. The tube isco-incident with the coupling axis A and also the axis of the centralrod. The tube extends from the distal end face and towards the oppositeend of the central rod. As shown in FIG. 27, the radial flange on theend of the distal rod is housed within the tubular section of theretaining member with the central rod extending through the hole insubstantially closed end.

A biasing means such as a spring 1192 operates between the closed end ofthe socket and an internal face of the closed end of the closing member1190. The spring biases the closing member towards the open end of thesocket. The closing member is stopped in the closed position by abutmentbetween the substantially closed end of the retaining member and theradial flange of the central member of the closing member. The closingmember is arranged to stop in the closed position such that the externalface of the closed end of the closing member is in the same plain as theopen end of the sockets.

In the closed position, the internal sealing ring 1128 seals the socketto the closing member between the open end of the socket and theaperture of the through-bore 1121. An external sealing ring 1193 sealsthe socket to the closing member on the opposite side of the aperture ofthe through-bore 1121. As such, in the closed position, fluid in thethrough-bore 1121 is sealed from escaping the through-bore at the socketend.

An engaging means 1194 is arranged on the outside of the female couplingmember and comprises a plate that extends perpendicular and parallel tocoupling axis A. The engaging means includes a through hole.

The male and female coupling members may be coupled by initiallyabutting the two flat ends of each coupling member, as shown in FIG. 28.Coupling may then be initiated by providing a closing force such thatthe members move to a fully inserted position, as shown in FIG. 29.During the further insertion, the closing member of the male couplingmember and the closing member of the female coupling member are urgedaxially and against the bias of the respective springs 1164 and 1192.Movement is stopped by abutment between the radial flange of the malecoupling member and the end of the respective closing member and also byabutment between the closed end of the socket and the end of therespective closing member. As can be seen in FIG. 29, and as previouslydescribed, in the fully inserted position the through-bores in each ofthe coupling members are aligned. Furthermore the external sealing ringof the probe and the internal sealing ring of the socket are arrangedabout the through-bores as previously described.

Furthermore, in the fully inserted position, the engagement means of themale coupling member and the engagement means of the female couplingmember are also aligned. As described in previous embodiments, abreakout pin may be inserted through the respective through-holes ineach of the engagement members to thereby provide breakout strength. Thepin will also need to be inserted to resist the force of the springsfrom urging the coupling members apart.

The hole 1119 through the sheath of the male coupling member is arrangedto accept a tubular part of the female coupling member through which theinternal through-—bore 1121 extends. This provides rotational alignmentbetween the two coupling members, which is needed in order to ensurealignment between the through-bores.

Such an embodiment provides several advantages. The embodiment providesflat ends to the couplings, which enables the couplings to be wipedclean easily. The through-bores in each coupling member are also closedwhen not coupled thereby ensuring fluid running through the bores doesnot escape during coupling and de-coupling of the assembly.

FIG. 30 shows a twelfth embodiment of the present invention, whereincoupling members substantially in accordance with the herein describedembodiments are manufactured in a composite structure such as carbon orglass fibre.

It is known that a ±55° wind angle achieves optimum strength for a tubesection. Accordingly, bent tubes, such as the male coupling member,would be manufactured with a ±55° wind angle maintained along both theproximal region 1204 with respect to the flow axis B and also along theprobe with respect to the coupling axis A.

FIG. 30 shows the fibre pattern in accordance with the twelfthembodiment of the present invention. The male coupling member comprisesa ±55° wind angle along the proximal region but then changes to a 0/90°wind angle along the probe wherein the majority of the fibres are laidalong the axial direction. Contrastingly the fibres of the femalecoupling member are laid with a ±55° wind angle along the open endregion but change to a 0/90° wind angle at the socket section with themajority of the fibres being laid in the radial direction.

The change in wind angle gives the coupling members greater strength andcounteracts the dominant hoop stresses in the area.

The present invention may be used in hydraulic or pneumatic machinerybut is preferably used in fluid delivery applications.

A significant advantage of the present invention is that the flow offluid through the coupling assembly is substantially through a straightconduit. This enables the conduit and the adjoining upstream anddownstream fluid passages to be ‘pigged’, which is a well-knownoperation within the oil pipeline sector and requires an unobstructedconduit through any couplings.

It will be readily apparent to the appropriately skilled person that acoupling assembly in accordance with the present invention may beconveniently composed of plastics, metals, or any other materials thatare know in the art. Further, the precise arrangement of the parts maybe varied from those depicted within the accompanying drawings. Forinstance, it is not required that the coupling assembly be substantiallysymmetrical, and indeed for some applications it may be advantageous tohave eccentrically shaped parts. The cross section of the male memberand the corresponding female member socket need not be cylindrical,though this is the preferred embodiment as it allows for rotation of themale member(s) within the female member.

1. A coupling assembly for releasably interconnecting fluid passagescomprises male and female coupling members, which are mated in use byinserting a probe of the male member into a socket of the female member,each coupling member including a first end arranged for connection to afluid passage and a through-bore extending from the first end, whereinthe through-bore of the male coupling member extends between the firstend and a circumferential face of the probe, wherein when mated in use,the through-bores of each coupling member are coincident along a firstlongitudinal axis and the probe and socket are coincident along a secondlongitudinal axis, which is inclined to the first axis, thethrough-bores providing a fluid conduit between the two fluid passagesand fluid being substantially retained in the conduit by sealing means.2-4. (canceled)
 5. The coupling assembly as claimed in claim 1, in whichthe sealing means comprises a first and second annular sealing ring,wherein when mated in use, the first annular sealing ring is arranged onone side of the intersection of the through-bore and socket of thefemale member and the second annular sealing ring is arranged on theother side of the intersection of the through-bore and socket of thefemale member.
 6. The coupling assembly as claimed in claim 5, in whichthe first annular sealing ring comprises an internal annular sealingring within the socket and the second annular sealing ring comprises anexternal annular sealing ring on the probe.
 7. (canceled)
 8. Thecoupling assembly as claimed in claim 1, in which the through-bores inthe male and female coupling members are substantially straight, whereinwhen the coupling members are mated in use the through-bores define astraight fluid conduit.
 9. (canceled)
 10. The coupling assembly asclaimed in claim 1, in which the coupling assembly further comprisesreleasable retaining means arranged to resist the uncoupling of themated coupling members. 11-12. (canceled)
 13. The coupling assembly asclaimed in claim 10, in which the retaining means comprises a firstpart, which, in use, is arranged fast with the male coupling member, anda second part, which, in use, is arranged fast with the female couplingmember, and wherein in use the first part and second part engage witheach other, said engagement comprising the retaining means. 14-16.(canceled)
 17. The coupling assembly as claimed in claim 13, in whichthe first part comprises a resilient clip that comprises first andsecond sections arranged about opposing sides of the first longitudinalaxis and are joined by a connecting section that in use abuts a flangeon the male coupling member, wherein said abutment comprises the firstarrangement of the clip and male member, and wherein at least one ofsaid first and second sections includes the radial teeth spaced from theconnecting section. 18-21. (canceled)
 22. The coupling assembly asclaimed in claim 1, wherein the angle of inclination between the probeand the through-bore of the male coupling member, and between the socketand the through-bore of the female coupling member, is the same and isin the range 5-35°.
 23. The coupling assembly as claimed in claim 1, inwhich the socket of the female coupling member further includes a closedend and an aperture from the socket, wherein, in use, the aperture isarranged in communication with a space between the closed end and adistal end of the probe, such that when the probe is inserted into thesocket ambient fluid within the socket is forced out of the aperture andthe egress rate of the ambient fluid from the aperture determines theinsertion force required to insert the probe into the socket. 24-26.(canceled)
 27. The coupling assembly as claimed in claim 1, in which themale and female coupling members further comprise co-operating alignmentfeatures wherein said co-operation limits the relative orientation aboutthe second longitudinal axis that the probe can be inserted into thesocket. 28-29. (canceled)
 30. The coupling assembly as claimed in claim1, in which one or both of the male and female coupling members comprisea valve, which prevents fluid flow along the through-bore in a closedposition and allows fluid flow along the through-bore in an openposition. 31-34. (canceled)
 35. The coupling assembly as claimed inclaim 30, in which each valve is operable between the open and closedposition by rotating an operable feature and wherein the operablefeature is operated by a part of the opposing coupling member, such thatthe valve is rotated from the open position to the closed position whenthe probe is uncoupled from the socket, the valve further comprisingbiasing means, which acts to bias the valve towards the closed position,wherein the operable feature is operated by a part of the opposedcoupling member such that the valve is moved towards the open positionwhen the probe is inserted into the socket. 36-37. (canceled)
 38. Thecoupling assembly as claimed in claim 5, in which the probe and sockettaper adjacent to one or both of the sealing rings so as to preventdamage or removal of the sealing ring by fluid pressure.
 39. (canceled)40. The coupling assembly as claimed in claim 1, in which the malecoupling member comprises a first and second part, the second part beingslidably mounted relative to the first and along the first longitudinalaxis, wherein a biasing means biases the second part toward a firstposition, wherein the female coupling member comprises a recess and whenmated in use, the second part engages with the recess to prevent themale and female members from decoupling.
 41. The coupling assembly asclaimed in claim 40, in which the recess comprises a first part that isintegral with or held fast to the female coupling member and a secondpart that is separable from the female coupling member, wherein aretaining member secures the second part to the first part.
 42. Thecoupling assembly as claimed in claim 41, wherein the retaining memberis resilient such that, when mated in use, and at a given breakoutforce, the second part moves away from the first part thereby enlargingthe recess and allowing, when mated in use, the probe to withdraw fromthe socket. 43-45. (canceled)
 46. The coupling assembly as claimed inclaim 1, in which the male and female coupling members each include arespective through-bore closing member.
 47. The coupling assembly asclaimed in claim 46, in which one or both of the closing members aremoveable between a closed position, in which the closing member extendsacross the fluid aperture and wherein the first and second annularsealing rings are arranged on one side of the respective fluid aperturesand a further sealing ring is arranged on an opposing side of therespective fluid apertures, and an open position in which the closingmembers do not extend across the fluid aperture. 48-53. (canceled)
 54. Amethod of releasably interconnecting fluid passages comprises insertinga probe of a male coupling member into a corresponding socket of afemale coupling member, the coupling members being connected to the endof the fluid passages and at the junction between the two fluidpassages, each coupling member including a first end arranged forconnection to a fluid passage and a through-bore extending from thefirst end, wherein when mated in use, the through-bores of each couplingmember are coincident along a first longitudinal axis and the probe andsocket are coincident along a second longitudinal axis, which isinclined to the first axis, the through-bores providing a fluid conduitbetween the two fluid passages and fluid being substantially retained inthe conduit by sealing means.
 55. (canceled)
 56. The method as claimedin claim 54 and further including a coupling assembly for releasablyinterconnecting fluid passages comprises male and female couplingmembers, which are mated in use by inserting a probe of the male memberinto a socket of the female member, each coupling member including afirst end arranged for connection to a fluid passage and a through-boreextending from the first end, wherein the through-bore of the malecoupling member extends between the first end and a circumferential faceof the probe, wherein when mated in use, the through-bores of eachcoupling member are coincident along a first longitudinal axis and theprobe and socket are coincident along a second longitudinal axis, whichis inclined to the first axis, the through-bores providing a fluidconduit between the two fluid passages and fluid being substantiallyretained in the conduit by sealing means.
 57. (canceled)